import crypto from 'node:crypto';
import { decryptSecret, encryptSecret, maskApiKey } from './llm-providers.mjs';

const CONFIG_TABLE = 'h5_memory_v2_admin_config';
const CONFIG_SCOPE = 'global';

const FIELD_SPECS = [
  { env: 'MEMORY_ENABLED', group: 'global', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_BACKEND', group: 'global', field: 'backend', type: 'string' },
  { env: 'MEMORY_PROFILE_ENABLED', group: 'global', field: 'profileEnabled', type: 'boolean' },
  { env: 'MEMORY_EVENT_LOG_ENABLED', group: 'global', field: 'eventLogEnabled', type: 'boolean' },
  { env: 'MEMORY_VECTOR_ENABLED', group: 'global', field: 'vectorEnabled', type: 'boolean' },
  { env: 'MEMORY_FAIL_OPEN', group: 'global', field: 'failOpen', type: 'boolean' },

  { env: 'MEMIND_CHAT_LLM_ROUTER_ENABLED', group: 'chatIntentRouter', field: 'enabled', type: 'boolean' },
  { env: 'MEMIND_CHAT_ROUTER_MODEL_PROVIDER_KEY_ID', group: 'chatIntentRouter', field: 'modelProviderKeyId', type: 'string' },
  { env: 'MEMIND_CHAT_ROUTER_MODEL', group: 'chatIntentRouter', field: 'model', type: 'string' },
  { env: 'MEMIND_CHAT_ROUTER_MODEL_API', group: 'chatIntentRouter', field: 'modelApiType', type: 'string' },
  { env: 'MEMIND_CHAT_ROUTER_MIN_CONFIDENCE', group: 'chatIntentRouter', field: 'minConfidence', type: 'number' },
  { env: 'MEMIND_CHAT_ROUTER_MEMORY_ENABLED', group: 'chatIntentRouter', field: 'memoryResolveEnabled', type: 'boolean' },
  { env: 'MEMIND_CHAT_ROUTER_MEMORY_LIMIT', group: 'chatIntentRouter', field: 'memoryResolveLimit', type: 'number' },
  { env: 'MEMIND_CHAT_ROUTER_TIMEOUT_MS', group: 'chatIntentRouter', field: 'timeoutMs', type: 'number' },
  { env: 'MEMIND_CHAT_ROUTER_FALLBACK_ROUTE', group: 'chatIntentRouter', field: 'fallbackRoute', type: 'string' },

  { env: 'MEMORY_CANDIDATE_ENABLED', group: 'candidateMemory', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_CANDIDATE_MODE', group: 'candidateMemory', field: 'mode', type: 'string' },
  { env: 'MEMORY_CANDIDATE_MIN_IMPORTANCE', group: 'candidateMemory', field: 'minImportance', type: 'number' },
  { env: 'MEMORY_CANDIDATE_MIN_CONFIDENCE', group: 'candidateMemory', field: 'minConfidence', type: 'number' },
  { env: 'MEMORY_CANDIDATE_MAX_PENDING', group: 'candidateMemory', field: 'maxPending', type: 'number' },
  { env: 'MEMORY_CANDIDATE_PERSISTENCE_ENABLED', group: 'candidateMemory', field: 'persistenceEnabled', type: 'boolean' },

  { env: 'MEMORY_AGENT_RESOLVE_ENABLED', group: 'runtimeControl', field: 'agentResolveEnabled', type: 'boolean' },
  { env: 'MEMORY_AGENT_INJECTION_MODE', group: 'runtimeControl', field: 'agentInjectionMode', type: 'string' },
  { env: 'MEMORY_AGENT_CANARY_USER_IDS', group: 'runtimeControl', field: 'agentCanaryUserIds', type: 'string' },
  { env: 'MEMORY_AGENT_RESOLVE_LIMIT', group: 'runtimeControl', field: 'agentResolveLimit', type: 'number' },
  { env: 'MEMORY_AGENT_RESOLVE_TIMEOUT_MS', group: 'runtimeControl', field: 'agentResolveTimeoutMs', type: 'number' },
  { env: 'MEMORY_PROMOTION_ENABLED', group: 'runtimeControl', field: 'promotionEnabled', type: 'boolean' },
  { env: 'MEMORY_COMPACTION_V2_ENABLED', group: 'runtimeControl', field: 'compactionV2Enabled', type: 'boolean' },
  { env: 'MEMORY_REFLECTION_ENABLED', group: 'runtimeControl', field: 'reflectionEnabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_WORKER_ENABLED', group: 'runtimeControl', field: 'lifecycleWorkerEnabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_ROLLOUT_MODE', group: 'runtimeControl', field: 'lifecycleRolloutMode', type: 'string' },
  { env: 'MEMORY_LIFECYCLE_ROLLOUT_USER_IDS', group: 'runtimeControl', field: 'lifecycleRolloutUserIds', type: 'string' },

  { env: 'MEMORY_POLICY_ENABLED', group: 'policy', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_POLICY_SAVE_EXPLICIT', group: 'policy', field: 'saveExplicit', type: 'boolean' },
  { env: 'MEMORY_POLICY_REJECT_SENSITIVE', group: 'policy', field: 'rejectSensitive', type: 'boolean' },
  { env: 'MEMORY_POLICY_REQUIRE_EVIDENCE', group: 'policy', field: 'requireEvidence', type: 'boolean' },
  { env: 'MEMORY_POLICY_RETENTION_DAYS', group: 'policy', field: 'retentionDays', type: 'number' },

  { env: 'MEMORY_RETRIEVER_ENABLED', group: 'retriever', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_RETRIEVER_EPISODIC_ENABLED', group: 'retriever', field: 'episodicEnabled', type: 'boolean' },
  { env: 'MEMORY_RETRIEVER_EPISODIC_MODE', group: 'retriever', field: 'episodicMode', type: 'string' },
  { env: 'MEMORY_RETRIEVER_EPISODIC_CANARY_USER_IDS', group: 'retriever', field: 'episodicCanaryUserIds', type: 'string' },
  { env: 'MEMORY_RETRIEVER_SEMANTIC_ENABLED', group: 'retriever', field: 'semanticEnabled', type: 'boolean' },
  { env: 'MEMORY_RETRIEVER_PREFERENCE_ENABLED', group: 'retriever', field: 'preferenceEnabled', type: 'boolean' },
  { env: 'MEMORY_RETRIEVER_GOAL_ENABLED', group: 'retriever', field: 'goalEnabled', type: 'boolean' },
  { env: 'MEMORY_RETRIEVER_LIMIT', group: 'retriever', field: 'limit', type: 'number' },
  { env: 'MEMORY_RETRIEVER_TOKEN_BUDGET', group: 'retriever', field: 'tokenBudget', type: 'number' },
  { env: 'MEMORY_RETRIEVER_TIMEOUT_MS', group: 'retriever', field: 'timeoutMs', type: 'number' },

  { env: 'MEMORY_LIFECYCLE_ENABLED', group: 'lifecycle', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_DEDUPE_ENABLED', group: 'lifecycle', field: 'dedupeEnabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_CONFLICT_REVIEW', group: 'lifecycle', field: 'conflictReview', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_DECAY_ENABLED', group: 'lifecycle', field: 'decayEnabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_FORGETTING_ENABLED', group: 'lifecycle', field: 'forgettingEnabled', type: 'boolean' },
  { env: 'MEMORY_LIFECYCLE_COMPACT_INTERVAL_HOURS', group: 'lifecycle', field: 'compactIntervalHours', type: 'number' },

  { env: 'MEMORY_PERSONA_ENABLED', group: 'persona', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_PERSONA_PROVIDER', group: 'persona', field: 'provider', type: 'string' },
  { env: 'MEMORY_PERSONA_SHADOW_MODE', group: 'persona', field: 'shadowMode', type: 'boolean' },
  { env: 'MEMORY_PERSONA_MAX_TOKENS', group: 'persona', field: 'maxTokens', type: 'number' },
  { env: 'MEMORY_PERSONA_CACHE_TTL_SECONDS', group: 'persona', field: 'cacheTtlSeconds', type: 'number' },

  { env: 'MEMORY_GRAPH_ENABLED', group: 'graph', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_GRAPH_PROVIDER', group: 'graph', field: 'provider', type: 'string' },
  { env: 'MEMORY_GRAPH_MAX_DEPTH', group: 'graph', field: 'maxDepth', type: 'number' },
  { env: 'MEMORY_GRAPH_RELATION_LIMIT', group: 'graph', field: 'relationLimit', type: 'number' },

  { env: 'MEMORY_USER_MANAGEMENT_ENABLED', group: 'userMemory', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_USER_REVIEW_ENABLED', group: 'userMemory', field: 'reviewEnabled', type: 'boolean' },
  { env: 'MEMORY_USER_CORRECTION_ENABLED', group: 'userMemory', field: 'correctionEnabled', type: 'boolean' },
  { env: 'MEMORY_USER_PIN_ENABLED', group: 'userMemory', field: 'pinEnabled', type: 'boolean' },
  { env: 'MEMORY_USER_FORGET_ENABLED', group: 'userMemory', field: 'forgetEnabled', type: 'boolean' },
  { env: 'MEMORY_USER_DELETE_PROPAGATION', group: 'userMemory', field: 'deletePropagation', type: 'boolean' },

  { env: 'MEMORY_PLUGIN_HEALTH_ENABLED', group: 'pluginHealth', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_PLUGIN_HEALTH_INTERVAL_SECONDS', group: 'pluginHealth', field: 'intervalSeconds', type: 'number' },
  { env: 'MEMORY_PLUGIN_HEALTH_TIMEOUT_MS', group: 'pluginHealth', field: 'timeoutMs', type: 'number' },
  { env: 'MEMORY_PLUGIN_HEALTH_FAILURE_THRESHOLD', group: 'pluginHealth', field: 'failureThreshold', type: 'number' },
  { env: 'MEMORY_PLUGIN_HEALTH_AUTO_FALLBACK', group: 'pluginHealth', field: 'autoFallback', type: 'boolean' },

  { env: 'MEMORY_PGVECTOR_ENABLED', group: 'pgvector', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_PGVECTOR_DATABASE_URL', group: 'pgvector', field: 'databaseUrl', type: 'secret' },
  { env: 'MEMORY_PGVECTOR_TABLE', group: 'pgvector', field: 'table', type: 'string' },
  { env: 'MEMORY_PGVECTOR_EMBEDDING_MODULE', group: 'pgvector', field: 'embeddingModule', type: 'string' },
  { env: 'MEMORY_PGVECTOR_POOL_MAX', group: 'pgvector', field: 'poolMax', type: 'number' },
  { env: 'MEMORY_PGVECTOR_LIMIT', group: 'pgvector', field: 'limit', type: 'number' },

  { env: 'MEMORY_QDRANT_ENABLED', group: 'qdrant', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_QDRANT_URL', group: 'qdrant', field: 'url', type: 'string' },
  { env: 'MEMORY_QDRANT_COLLECTION', group: 'qdrant', field: 'collection', type: 'string' },
  { env: 'MEMORY_QDRANT_EMBEDDING_MODULE', group: 'qdrant', field: 'embeddingModule', type: 'string' },
  { env: 'MEMORY_QDRANT_API_KEY', group: 'qdrant', field: 'apiKey', type: 'secret' },
  { env: 'MEMORY_QDRANT_TIMEOUT_MS', group: 'qdrant', field: 'timeoutMs', type: 'number' },
  { env: 'MEMORY_QDRANT_LIMIT', group: 'qdrant', field: 'limit', type: 'number' },

  { env: 'MEMORY_WEAVIATE_ENABLED', group: 'weaviate', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_WEAVIATE_URL', group: 'weaviate', field: 'url', type: 'string' },
  { env: 'MEMORY_WEAVIATE_COLLECTION', group: 'weaviate', field: 'collection', type: 'string' },
  { env: 'MEMORY_WEAVIATE_EMBEDDING_MODULE', group: 'weaviate', field: 'embeddingModule', type: 'string' },
  { env: 'MEMORY_WEAVIATE_API_KEY', group: 'weaviate', field: 'apiKey', type: 'secret' },
  { env: 'MEMORY_WEAVIATE_TIMEOUT_MS', group: 'weaviate', field: 'timeoutMs', type: 'number' },
  { env: 'MEMORY_WEAVIATE_LIMIT', group: 'weaviate', field: 'limit', type: 'number' },

  { env: 'MEMORY_MEM0_ENABLED', group: 'mem0', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_MEM0_API_KEY', group: 'mem0', field: 'apiKey', type: 'secret' },
  { env: 'MEMORY_MEM0_PROJECT_ID', group: 'mem0', field: 'projectId', type: 'string' },
  { env: 'MEMORY_MEM0_BASE_URL', group: 'mem0', field: 'baseUrl', type: 'string' },
  { env: 'MEMORY_MEM0_WRITE_PATH', group: 'mem0', field: 'writePath', type: 'string' },
  { env: 'MEMORY_MEM0_COMPACT_PATH', group: 'mem0', field: 'compactPath', type: 'string' },
  { env: 'MEMORY_MEM0_MODEL_PROVIDER_KEY_ID', group: 'mem0', field: 'modelProviderKeyId', type: 'string' },
  { env: 'MEMORY_MEM0_MODEL', group: 'mem0', field: 'model', type: 'string' },
  { env: 'MEMORY_MEM0_MODEL_API', group: 'mem0', field: 'modelApiType', type: 'string' },
  { env: 'MEMORY_MEM0_TIMEOUT_MS', group: 'mem0', field: 'timeoutMs', type: 'number' },

  { env: 'MEMORY_LETTA_ENABLED', group: 'letta', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_LETTA_API_KEY', group: 'letta', field: 'apiKey', type: 'secret' },
  { env: 'MEMORY_LETTA_PROJECT_ID', group: 'letta', field: 'projectId', type: 'string' },
  { env: 'MEMORY_LETTA_AGENT_ID', group: 'letta', field: 'agentId', type: 'string' },
  { env: 'MEMORY_LETTA_BASE_URL', group: 'letta', field: 'baseUrl', type: 'string' },
  { env: 'MEMORY_LETTA_RESOLVE_PATH', group: 'letta', field: 'resolvePath', type: 'string' },
  { env: 'MEMORY_LETTA_WRITE_PATH', group: 'letta', field: 'writePath', type: 'string' },
  { env: 'MEMORY_LETTA_COMPACT_PATH', group: 'letta', field: 'compactPath', type: 'string' },
  { env: 'MEMORY_LETTA_MODEL_PROVIDER_KEY_ID', group: 'letta', field: 'modelProviderKeyId', type: 'string' },
  { env: 'MEMORY_LETTA_MODEL', group: 'letta', field: 'model', type: 'string' },
  { env: 'MEMORY_LETTA_MODEL_API', group: 'letta', field: 'modelApiType', type: 'string' },
  { env: 'MEMORY_LETTA_TIMEOUT_MS', group: 'letta', field: 'timeoutMs', type: 'number' },

  { env: 'MEMORY_NEO4J_ENABLED', group: 'neo4j', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_NEO4J_URI', group: 'neo4j', field: 'uri', type: 'string' },
  { env: 'MEMORY_NEO4J_HTTP_URL', group: 'neo4j', field: 'httpUrl', type: 'string' },
  { env: 'MEMORY_NEO4J_USER', group: 'neo4j', field: 'user', type: 'string' },
  { env: 'MEMORY_NEO4J_PASSWORD', group: 'neo4j', field: 'password', type: 'secret' },
  { env: 'MEMORY_NEO4J_DATABASE', group: 'neo4j', field: 'database', type: 'string' },
  { env: 'MEMORY_NEO4J_TIMEOUT_MS', group: 'neo4j', field: 'timeoutMs', type: 'number' },

  { env: 'MEMORY_REDIS_STREAMS_ENABLED', group: 'redisStreams', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_REDIS_STREAMS_URL', group: 'redisStreams', field: 'url', type: 'string' },
  { env: 'MEMORY_REDIS_STREAMS_STREAM', group: 'redisStreams', field: 'stream', type: 'string' },

  { env: 'MEMORY_LANGGRAPH_ENABLED', group: 'langgraph', field: 'enabled', type: 'boolean' },
  { env: 'MEMORY_LANGGRAPH_URL', group: 'langgraph', field: 'url', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_POLICY_ID', group: 'langgraph', field: 'policyId', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_API_KEY', group: 'langgraph', field: 'apiKey', type: 'secret' },
  { env: 'MEMORY_LANGGRAPH_RESOLVE_PATH', group: 'langgraph', field: 'resolvePath', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_MODEL_PROVIDER_KEY_ID', group: 'langgraph', field: 'modelProviderKeyId', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_MODEL', group: 'langgraph', field: 'model', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_MODEL_API', group: 'langgraph', field: 'modelApiType', type: 'string' },
  { env: 'MEMORY_LANGGRAPH_TIMEOUT_MS', group: 'langgraph', field: 'timeoutMs', type: 'number' },
];

const GROUPS = [
  'global',
  'chatIntentRouter',
  'candidateMemory',
  'runtimeControl',
  'policy',
  'retriever',
  'lifecycle',
  'persona',
  'graph',
  'userMemory',
  'pluginHealth',
  'pgvector',
  'qdrant',
  'weaviate',
  'mem0',
  'letta',
  'neo4j',
  'redisStreams',
  'langgraph',
];

function defaultConfigShape() {
  return Object.fromEntries(GROUPS.map((group) => [group, {}]));
}

function normalizeBoolean(value, fallback = false) {
  if (value == null || value === '') return fallback;
  if (typeof value === 'boolean') return value;
  const normalized = String(value).trim().toLowerCase();
  if (['1', 'true', 'yes', 'on'].includes(normalized)) return true;
  if (['0', 'false', 'no', 'off'].includes(normalized)) return false;
  return fallback;
}

function normalizeNumber(value) {
  if (value == null || value === '') return '';
  const parsed = Number(value);
  return Number.isFinite(parsed) ? String(parsed) : '';
}

function normalizeString(value) {
  if (value == null) return '';
  return String(value).trim();
}

function normalizeSecretPatch(value) {
  if (value === undefined) return undefined;
  if (value === null) return '';
  return String(value);
}

function cloneConfig(config = null) {
  return structuredClone?.(config ?? defaultConfigShape())
    ?? JSON.parse(JSON.stringify(config ?? defaultConfigShape()));
}

function parseJsonLike(value, fallback) {
  if (value == null || value === '') return fallback;
  if (typeof value === 'string') {
    try {
      return JSON.parse(value);
    } catch {
      return fallback;
    }
  }
  if (typeof value === 'object') return value;
  return fallback;
}

function flattenConfig(config, secrets) {
  const env = {};
  for (const spec of FIELD_SPECS) {
    const value = spec.type === 'secret'
      ? secrets?.[spec.group]?.[spec.field]
      : config?.[spec.group]?.[spec.field];
    if (spec.type === 'boolean') {
      env[spec.env] = normalizeBoolean(value, false) ? '1' : '0';
    } else if (spec.type === 'number') {
      env[spec.env] = normalizeNumber(value);
    } else {
      env[spec.env] = normalizeString(value);
    }
  }
  if (!env.MEMORY_PGVECTOR_ENABLED) {
    env.MEMORY_PGVECTOR_ENABLED = env.MEMORY_VECTOR_ENABLED;
  }
  return env;
}

function applyEnv(config, secrets, env = process.env) {
  for (const spec of FIELD_SPECS) {
    const raw = env?.[spec.env];
    if (spec.type === 'secret') {
      if (raw != null && String(raw).trim() !== '') {
        secrets[spec.group][spec.field] = String(raw).trim();
      }
      continue;
    }
    if (spec.type === 'boolean') {
      config[spec.group][spec.field] = normalizeBoolean(raw, Boolean(config[spec.group][spec.field]));
    } else if (spec.type === 'number') {
      const normalized = normalizeNumber(raw);
      if (normalized !== '') config[spec.group][spec.field] = normalized;
    } else if (raw != null && String(raw).trim() !== '') {
      config[spec.group][spec.field] = String(raw).trim();
    }
  }
  if (config.pgvector.enabled === undefined) {
    config.pgvector.enabled = normalizeBoolean(env?.MEMORY_VECTOR_ENABLED, false);
  }
  if (env?.MEMIND_CHAT_ROUTER_MEMORY_ENABLED == null || String(env.MEMIND_CHAT_ROUTER_MEMORY_ENABLED).trim() === '') {
    config.chatIntentRouter.memoryResolveEnabled = true;
  }
  if (!normalizeString(config.chatIntentRouter.modelApiType)) {
    config.chatIntentRouter.modelApiType = 'chat';
  }
  if (!normalizeString(config.chatIntentRouter.minConfidence)) {
    config.chatIntentRouter.minConfidence = '0.65';
  }
  if (!normalizeString(config.chatIntentRouter.memoryResolveLimit)) {
    config.chatIntentRouter.memoryResolveLimit = '8';
  }
  if (!normalizeString(config.chatIntentRouter.timeoutMs)) {
    config.chatIntentRouter.timeoutMs = '2500';
  }
  if (config.chatIntentRouter.enabled === undefined) {
    config.chatIntentRouter.enabled = false;
  }
  const fallbackRoute = normalizeString(config.chatIntentRouter.fallbackRoute);
  if (!fallbackRoute || fallbackRoute === 'direct_chat') {
    config.chatIntentRouter.fallbackRoute = 'agent_orchestration';
  }
  return { config, secrets };
}

function buildMaskedView(config, secrets) {
  const view = cloneConfig(config);
  for (const spec of FIELD_SPECS) {
    if (spec.type !== 'secret') continue;
    const raw = normalizeString(secrets?.[spec.group]?.[spec.field]);
    view[spec.group][`${spec.field}Configured`] = raw.length > 0;
    view[spec.group][`${spec.field}Masked`] = raw ? maskApiKey(raw) : '';
  }
  return view;
}

async function ensureConfigTable(pool) {
  await pool.query(`
    CREATE TABLE IF NOT EXISTS ${CONFIG_TABLE} (
      config_scope VARCHAR(32) PRIMARY KEY,
      config_json JSON NOT NULL,
      secrets_ciphertext MEDIUMTEXT NULL,
      secrets_iv VARCHAR(255) NULL,
      secrets_tag VARCHAR(255) NULL,
      updated_by CHAR(36) NULL,
      updated_at BIGINT NOT NULL
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci
  `);
}

function hashState(config, secrets) {
  return crypto
    .createHash('sha256')
    .update(JSON.stringify({ config, secrets }))
    .digest('hex');
}

async function loadStoredState(pool) {
  await ensureConfigTable(pool);
  const [rows] = await pool.query(
    `SELECT config_json, secrets_ciphertext, secrets_iv, secrets_tag, updated_by, updated_at
       FROM ${CONFIG_TABLE}
      WHERE config_scope = ?
      LIMIT 1`,
    [CONFIG_SCOPE],
  );
  const row = rows[0];
  if (!row) return null;
  let secrets = defaultConfigShape();
  if (row.secrets_ciphertext && row.secrets_iv && row.secrets_tag) {
    secrets = {
      ...defaultConfigShape(),
      ...parseJsonLike(
        decryptSecret(
          {
            ciphertext: row.secrets_ciphertext,
            iv: row.secrets_iv,
            tag: row.secrets_tag,
          },
        ),
        {},
      ),
    };
  }
  return {
    config: { ...defaultConfigShape(), ...parseJsonLike(row.config_json, {}) },
    secrets,
    updatedAt: Number(row.updated_at ?? 0) || null,
    updatedBy: row.updated_by ?? null,
  };
}

function mergePatch(currentConfig, currentSecrets, patch = {}) {
  const nextConfig = cloneConfig(currentConfig);
  const nextSecrets = cloneConfig(currentSecrets);
  for (const spec of FIELD_SPECS) {
    const section = patch?.[spec.group];
    if (!section || !(spec.field in section)) continue;
    if (spec.type === 'secret') {
      const value = normalizeSecretPatch(section[spec.field]);
      if (value === undefined) continue;
      nextSecrets[spec.group][spec.field] = normalizeString(value);
      continue;
    }
    const value = section[spec.field];
    if (spec.type === 'boolean') {
      nextConfig[spec.group][spec.field] = normalizeBoolean(value, false);
    } else if (spec.type === 'number') {
      nextConfig[spec.group][spec.field] = normalizeNumber(value);
    } else {
      nextConfig[spec.group][spec.field] = normalizeString(value);
    }
  }
  return { nextConfig, nextSecrets };
}

export function createMemoryV2AdminConfigService(pool, { env = process.env } = {}) {
  async function loadState() {
    const defaults = applyEnv(defaultConfigShape(), defaultConfigShape(), env);
    const stored = await loadStoredState(pool);
    if (!stored) {
      return {
        config: defaults.config,
        secrets: defaults.secrets,
        updatedAt: null,
        updatedBy: null,
      };
    }
    return {
      config: { ...defaults.config, ...stored.config },
      secrets: { ...defaults.secrets, ...stored.secrets },
      updatedAt: stored.updatedAt,
      updatedBy: stored.updatedBy,
    };
  }

  return {
    async getAdminConfig() {
      const state = await loadState();
      return {
        config: buildMaskedView(state.config, state.secrets),
        updatedAt: state.updatedAt,
        updatedBy: state.updatedBy,
      };
    },

    async updateAdminConfig(patch = {}, { updatedBy = null } = {}) {
      const state = await loadState();
      const { nextConfig, nextSecrets } = mergePatch(state.config, state.secrets, patch);
      await ensureConfigTable(pool);
      const now = Date.now();
      const encryptedSecrets = encryptSecret(JSON.stringify(nextSecrets));
      await pool.query(
        `INSERT INTO ${CONFIG_TABLE}
          (config_scope, config_json, secrets_ciphertext, secrets_iv, secrets_tag, updated_by, updated_at)
         VALUES (?, ?, ?, ?, ?, ?, ?)
         ON DUPLICATE KEY UPDATE
          config_json = VALUES(config_json),
          secrets_ciphertext = VALUES(secrets_ciphertext),
          secrets_iv = VALUES(secrets_iv),
          secrets_tag = VALUES(secrets_tag),
          updated_by = VALUES(updated_by),
          updated_at = VALUES(updated_at)`,
        [
          CONFIG_SCOPE,
          JSON.stringify(nextConfig),
          encryptedSecrets.ciphertext,
          encryptedSecrets.iv,
          encryptedSecrets.tag,
          updatedBy,
          now,
        ],
      );
      return this.getAdminConfig();
    },

    async getRuntimeState() {
      const state = await loadState();
      const overrides = flattenConfig(state.config, state.secrets);
      return {
        source: 'admin-db',
        updatedAt: state.updatedAt,
        updatedBy: state.updatedBy,
        fingerprint: `${state.updatedAt ?? 'env'}:${hashState(state.config, state.secrets)}`,
        overrides,
      };
    },
  };
}

export const memoryV2AdminConfigInternals = {
  CONFIG_SCOPE,
  CONFIG_TABLE,
  FIELD_SPECS,
  defaultConfigShape,
  flattenConfig,
  applyEnv,
  mergePatch,
  buildMaskedView,
};